Perennial crops (such as grapes) are negatively impacted by the presence and growth of weeds in the areas surrounding and adjacent to the crops. Similar concerns also apply to immature trees, shrubs, and many crops grown on lattice works, and various other types of scaffolding. Crops that fall into these categories frequently have trunks/stalks that are relatively substantial and robust, but are more vulnerable than the trunks of mature trees.
These types of crops are frequently grown in widely spaced rows and may produce products (such as fruits) that are in relatively close proximity to the ground. Weeds around the crops compete with the crops for light, moisture, and soil nutrients. The weeds may also bring undesirable insects and diseases, and interfere with workers' ability to care for and maintain the crops. Weeds also obstruct harvesting machinery and add time and expense to the harvesting process.
Herbicides are frequently used to control the weeds around perennial crops however, even if the herbicides do not directly damage the crops, the plants may absorb some or all of the herbicide chemicals and express the chemicals in their fruits and other products. Over-spraying and spray drift may cause the herbicides to be deposited directly on the fruits/products. Further, the use of herbicides and other chemical sprays always evokes concerns regarding the unintended effects of the sprays on the local ground and surface water as well as the flora and fauna in the environment associated with the affected fields. Additionally, there is a general market preference (and an associated higher price) for products grown “organically” without the use of chemical sprays.
Weeds can be removed manually by a worker on foot using a mechanized or non-mechanized tool. Although these methods are relatively simple and in some respects inexpensive, they are also slow, inefficient, and increase labor costs. Most hand-carried tools are limited to cutting the weeds on the surface and lack the practical ability to cultivate large areas in a relatively short period of time.
More powerful tractor-mounted tools are also used to remove weeds around perennial crops. Although traditional brush-hog type mowers can quickly cut the weeds, working in close proximity to the trunks/stalks of the crops can be a slow process and any operator error may result in the loss of a valuable plant. Additionally, some areas immediately adjacent to the crops simply cannot be addressed by this process and the mowers are not capable of actually penetrating the ground and cultivating the soil.
Recently, new and powerful tractor-mounted cultivator systems have become available to cultivate the areas around the crops. These cultivator systems commonly use an array of mechanical and electrically-based sensors to prevent the cultivating mechanism from contacting the selected plant. However, these systems are generally complex and prone to problems in a field environment. Further, the systems require support and integration equipment that significantly increases the size and weight, and technical complexity of the overall device so that the systems cannot be used on small tractors.
The need exists for a simple and efficient cultivating system that allows a tractor-mounted device to operate in close proximity to targeted plants such as perennial crops, shrubs, and immature trees without damaging the targeted plants. The current invention comprises a system compatible with relatively small and simple farm tractors that enables an operator to quickly and efficiently cultivate the area immediately adjacent to the targeted plants.